Generally speaking, the present invention pertains to a circuit controller which actuates machine functions of an appliance; a motor and a gear train driving the controller, the gear train including a program means; follower means engaging the program means to be actuated thereby; and electrical switch means responsive to the follower means to be opened and closed thereby.
This invention relates, in general, to a timing mechanism and in particular to a timing mechanism particularly adaptable for controlling a laundry dryer through a timed fabric treatment cycle.
Some automatic clothes dryers include an anti-wrinkle control system that provides for rearranging and refluffing permanent press fabrics every few minuts if they are not removed from the dryer at the end of the automatic or timed drying period. More specifically, at the end of a permanent press cycle, a buzzer sounds to remind a housewife, for example, that her clothes are ready. If she is busy or out of the home, the anti-wrinkle control starts the dryer at predetermined intervals, for example every five minutes and tumbles the clothes for a predetermined interval, for example, 10 seconds. At the end of each 10 seconds of tumbling, the dryer again buzzes to remind the housewife to remove the clothes. The dryer continues to "nag" in this manner for a predetermined period of time, for example, up to two and one half hours. However, for the times illustrated, total running time for the dryer would only be five minutes.
One system providing an anti-wrinkle portion of a drying cycle employed two timer motors. One motor drove the timer cams which sequentially operated the dryer at a constant speed, while a second "pulser" motor drove a cam to intermittently complete a circuit to the timer motor to advance the timer cams intermittently and to complete a circuit and intermittently cycle the main dryer motor operating the dryer and to run out the timer motor until a predetermined accumulative minutes of timer "on time" had expired. A "two motor" timer useful for such a system is described in U.S. Pat. No. 3,732,383 issued May 8, 1973. Because of the decreasing amount of available space required in automatic clothes dryer operation and because of the increased amount of cost of the additional motor, it has become highly desirable to replace this conventional method of operation with a system utilizing only the single timer motor.
In another system, two cams are carried by a shaft, one of them being fixed to the shaft and the other being freely rotatable about the shaft. A gear train of a motor drive means is supplied with two separate output pinions, the two output pinions serving to simultaneously drive the two cams at different speeds. The faster speed can be used to provide selective pulsing which can be used in anti-wrinkle control. While this system has been used satisfactorily, it has been found to be somewhat expensive for certain applications.